Former first lady Melania Trump was absent from a family Christmas photo — featuring former President Donald Trump and three of his kids — because she was by her sick mother’s side in the hospital, The Post has learned.

Melania, 53, was with her ailing mom Amalija Knavs when the festive snapshot was taken at the ex-commander in chief’s sprawling Mar-a-Lago estate in West Palm Beach, Fla. over the holiday, a source familiar with the matter said.

The photo, which was shared on Instagram Tuesday by Donald Trump Jr’s fiancée, Kimberly Guilfoyle, showed a smiling Trump, 77, flanked by most of his children — including his towering 17-year-old son, Barron, whom he shares with the former first lady.

Melania’s father, Viktor Knavs, was also included in the family portrait.

“Melania has always been very devoted to her entire family,” a source close to Mrs. Trump elaborated to Fox News Digital. “It should be no surprise that she spent this Christmas with her ailing mother.” 

A spokesperson for the former first lady only told The Post Melania was tending to a family matter at the time the picture was taken.

The other members of the Trump clan who were front and center included Don Jr. and Guilfoyle; Ivanka Trump, her husband Jared Kushner and their three children; and Tiffany Trump and her husband Michael Boulos.

Trump’s other son, Eric, and his wife Lara were not seen.

The ex-first lady’s absence came just days after Page Six sources revealed Melania was planning to step up her public appearances in 2024 as her husband ramps up his White House bid.

“Trump and his family are so secure that he will become president again that insiders at Mar-a-Lago say he’s reached an agreement with Melania to step up top-tier diplomatic appearances in 2024,” a source said.

“Melania realizes it’s her time to join the ranks of historic first ladies and leave her mark on history … She feels better prepared for her potential role the second time around.”

The source added that Melania could be expected to devote more time to her husband’s campaign this time around because Barron is now a teenager.

In recent weeks, Melania joined all other living first ladies at the Atlanta memorial service for Rosalynn Carter.

She also delivered rare public remarks at a citizens’ naturalization ceremony at the National Archives in Washington.

Meanwhile, Trump scored an early Christmas present last week when the Supreme Court refused to make a quick decision on whether he will get immunity from the federal charges leveled against him over his challenge of the 2020 election results.

Trump’s legal team has argued the former president shouldn’t be put on trial for his election challenges — which culminated in the Jan. 6, 2021, Capitol riot — because they were “official acts.”